Instrument for drawing noncircular curves



Nov. 7, 1950 P. BLAMPIED 2,529,130

INSTRUMENT FOR DRAWING NONCIRCULAR CURVES Filed June 25, 1947 Patented Nov. 7,

Es" PATENT OFFICE INSTRUMENTFOR DRAWING NoNcIRoULAR i f i ,.ouRvns lPhilip enemiga-Flushing, N. Y,

My-invention is an improvement belonging to y the class of instruments for making curved lines i on paper andthe like, in the laying out of drawings and pictorial designs; and particularly an implement for producing arcs and curves of .any desired configuration, with a single continuous motion of the part 'that carriesthe marking substance, such as the lead. or ink."

An important object of the invention is to providel a-drafting implement having the general construction of a compass, but especially adapted to describe in the same manneras an ordinaryk compass aecurve representing any open orjclosed figure or outline of non-circular form.

A further object is to provide an implement of the type mentioned that is simple in design, inexpensive to turn out, easy to manipulate, certain in operation, and capable of use by persons of no great skill at any time to attain the required end.

The nature and advantages of the invention are set forth in the ensuing specification, which discloses a preferred embodiment of the device. But this disclosure is explanatory and various changes may be made in details of the combination shown, without deviation from the principle of the improvement, or alteration of its fundamental character, or omission of any of the essential characteristics thereof.

On the drawings:

Figure l is a perspective view of a drafting instrument according to this invention;

Figures 2 and 3 show details which are embraced in the invention; and

Figure 4 shows another detail of construction.

The instrument includes a pair of legs I and 2, pivotally connected to each other at one eX- tremity, as indicated at 3. The lower end of one of the legs I has a foot member 4, pivotally joined thereto by a rivet 5. The foot is made of a fiat plate of metal, or other suitable material disposed preferably in the plane of the two legs, and has pointed projections 6 at its opposite ends extending away from the leg I carrying it. The other leg 2 has means for carrying a substance for marking the surface of the paper or sheet upon which the instrument is employed, such as the two nibs "I of a drafting pen to receive ink. Obviously a part carrying a piece of lead can also be utilized. The pen or the lead-bearing member can be of any well known type, detachably secured to the leg 2.

On the leg I is a disk or template 8 the peripheral edge of which has the shape of the gure to be described by the leg I. This disk can be Application June"25","1947, serial No.' 756,888

2 claims. (o1. sag-ecn an`'oval or ellipse, or -have any different shape A desired, such as 8a in Figure 3. When this disk is secured in position on the leg I with the foot 4 f resting on the sheet, and the leg 2l is swung y Varound it, being kept at the same time in continuous contact Hwith the edge of the disk, 'a curve will be drawn on the sheet reproducing the configuration of the disk 8; Y

At the Acenter the disk or template has a hub yor bearing 9,-in which is a binding screw Ill. By i means of this bearing the guide element or disk` canbe shifted along the leg I, to control the size i of -the figure described b y the leg 2. 'Iluefarther 1 the disk! is from the connection of the legs I and 2, the smaller the figure will be.

Attached to the implement adjacent the pivotal connection of the legs I and 2 is a retaining element II, which has the form of a flat bent spring, the ends of which abut and press upon the outer sides of the legs and force the two legs towards each other. Thus the leg I is maintained in engagement with the edge of the guiding element 8. The spring means I I preferably extends around outside the pivotal connection of the legs.

In Figure 4 the connection of the leg 2 at the top `with the other leg I is shown in section fully, this connection being such that the leg I does not rotate and both points 6 on the pivoted foot 4 are pressed upon the paper or other surface and remain stationary. The top of the leg I has a reduced axial projection or journal Ia, upon which is swivelled a coupling member I3, that has a bore I 3a receiving the journal Ia. The member I3 has a threaded shouldered projection I3b on which the knob or finger piece I2 is screwed. The leg 2 has a pair of spaced lugs I4 at the top receiving the member I3 between them, and screws I5 secure these lugs to the member I3, the inner ends of these screws being reduced and fitting into a circumferential groove I6 in the journal la. The leg I has a shoulder at the base of the journal Ia and a reduced projection I1 on which the member I 3 seats to form a groove I8 into which the end II a of the spring II is received. This spring has an opening through which the threaded projection I3b extends. With this method of coupling the legs I and 2, the knob I2 can be turned to rotate the member I3 on the journal I a so as to swing the leg 2 around the leg I, which is held stationary by the points 6 of the foot 4. The spring II of course moves with leg 2, the endIIa sliding in the groove I8 above mentioned.

The implement is therefore well calculated to serve all the purposes of the invention, to delineate open or closed gures of any selected shape.

Having described my invention, what I believe to be new is:

1. A drafting implement comprising a pair of legs, one leg having means for carrying a substance for marking a surface, a foot pivotally connected to the other end of the other leg, said foot having pointed projections at itsfopposite ends extending awayv from said other leg, and means for pivotally connecting said legs so that one can be turned around the other as an axis,

said means comprising a journal on the other 1eg,.

a member pivotally mounted on said journal,

the one leg having a pair of lugs receiving said l15 member between them, pivot screws uniting.v said lugs to said member, said journal having a groove to receive the inner ends of said screws, a shoul-y ends with both said legs, and a knob,engagingV said projection securing said element thereon. i

2. A drafting implement comprising a pair of legs, one leg having means for carryinga sub- Y stance for marking a surface, a foot pivotalliyVv cor-inected to the othery end of the other leg, said foot having pointed projectionsv'at its opposite endsextending away from said otherrleg, and

means for pivotally connecting saidlegs so that one can be turned around'the other as an "axis,

said means comprising a journal on theV otherj leg, amember pivotally mounted on said journal,

the one leg having a pair of lugs receiving said member between them, pivot screws uniting said lugs to said member, said journal having a groove to receive the inner ends of said screws, a shouldered projection on said member, a curved spring element having an opening receiving said projection and having pressing engagement at its ends with both said legs, and a knob engaging said projectionsecuringv Saidelement thereon, a disk on said'other leg above said foot, said disk having the outline of the gure to be reproduced, the disk having a hub-shaped bearing at the center, a binding screw carried by the bearing to retain the disk in adjusted position on said othery leg, said element holding the firstenamed legv in continuous contact with the edge of the disk.

PHILIP BLAMPIED.

REFERENCES CITED The following, references are of record. in the iii-eef this patent:

l UNITED STATES PATENTS NumberV Germany ---l Nov. 13, 1928, 

